Objectives: Many jurisdictions are moving toward greater public involvement in health technology assessment (HTA) processes. This study aims to provide a broad, cross-sectional indication of the extent and methods of public engagement in HTA, with a focus on which public are engaged, by what mechanisms, and the purpose of public engagement. Methods: An international Web-based survey of 217 organizations involved in HTA was undertaken. Contact e-mail addresses for targeted organizations were identified from the Internet. Results: Individuals from 39 (18%) of the contacted organizations completed a survey. The majority (67%) of responding HTA organizations undertake public engagement activities, predominantly involving lay representatives of organized groups (81%), and to a lesser extent individual patients/consumers (54%) or citizens/community members (54%). For organizations undertaking public engagement, mechanisms based on communication or consultation were the most common, although some organizations have used or intend to use participatory approaches, particularly the Citizens' Jury (8%) or Consensus Council (20%) methods. Respondents identified with a number of rationales and barriers for undertaking public engagement. Conclusions: This survey provides further insight into the public engagement approaches that are used by HTA organizations in practice. In particular, it suggests a limited adoption of participatory methods to date, and interest in the use of social media. Study findings require further confirmation, due to limitations related to survey response. There is considerable opportunity for further research into pragmatic, robust, and meaningful approaches to public engagement to strengthen HTA policy and decision-making frameworks. An agenda for future research evolving from the survey responses is proposed.